Method for using power lines for wireless communication

ABSTRACT

The method is for providing broadband access into a dwelling. A radio base station is provided that is in connection with a power-line communication (PLC) gateway. The radio base station transmits an information signal to the PLC gateway. The PLC gateway receives the signal and transmits the information signal via power-line to an inside of the dwelling.

TECHNICAL FIELD

The invention relates to a method for using power lines for wirelesscommunication such as telecommunication and broadband.

BACKGROUND AND SUMMARY OF THE INVENTION

The use of wireless communication is developing rapidly and higherperformance and speed are required to meet the increasing demand fortransporting large amounts of communication data for differentapplications such as video streaming. The currently availablewireless-communication systems deteriorate substantially when the radiosignals must penetrate obstacles such as walls inside homes. This hasnot been a major problem in the past as the amount of data required toprovide voice and text information are not large compared with forexample video streaming, so radio signal deterioration could betolerated to a larger extent. More particularly, with the progress ofwireless access technologies to provide higher data speeds, many telecomoperators are focusing on efficiently using these to offer broadbandaccess to their customers. This may rely on a copper and even fiberreplacement scheme to offer triple and even quadruple play servicescompared to the previously provided information speed. However, typicaldeterioration of performance of a high speed data wireless technologycan in most cases exceed 80% of its potential when the radio signaltravels through walls. The deterioration is related to the nature andthickness of the obstacle whereby it could be due to absorption orreflection/interference and fading. When applied to a high speed datawireless access network, a typical access technology may lose more than80% of its performance, i.e. more than 80% of the data throughput itprovides at the radio base station site.

A cost-efficient solution to this problem has the potential for allowinga massive broadband deployment to households, offices, schools, and anyother indoor environment. Additionally, the current solutions adopted toprovide high-capacity wireless coverage indoors are complex and veryexpensive. Power line communication on the other hand does not have thisperformance deterioration problem when penetrating walls inside housesbut is not used for broadband and telecommunication because it issubject to significant performance losses over longer distances andacross transformer stations.

The problems resulting from the above can fall under two categories:

A) There are a multitude of competing radio access technologies; and

B) The currently adopted solutions to deploy broadband coverage indoorare complicated and expensive.

There is currently an abundance of radio access technologies that offerbroadband services. This is a phenomenon that makes it difficult todrive economies of scale, roaming, and simplicity. However, mostconsumers and regulator authorities desire inexpensive and simplesystems that may be in the form of real plug-and-play solutions anywhereat anytime without much focus on full mobility since a large portion ofthe world's population has not yet acquired a lifestyle to require andvalue this mode of usage.

A great challenge for the current suppliers and operators of wirelessbroadband access is to find an efficient, safe, and practical way tobring high speed data throughput indoors, into homes, schools,workplaces, airports, and even moving vehicles such as trains, airplanesand busses.

As wireless technologies move towards higher order modulations such as32 or 64 QAM striving for more efficient usage of frequency spectrumresources and higher bits/Hz, a radio signal suffers a larger and largerdeterioration above 80% of its performance due to the large loss of thepayload data it carries when penetrating walls. This also means thateven higher order modulations constitute no viable option for the futureas far as radio signals that must travel through walls.

There is a growing level of concern among users worldwide due to theincreasing closeness of an increasing number of high output powertransmitting antennas to people especially due to MIMO techniques, aswell as the increasing need to acquire new additional radio base stationsites to carry a large number of visible antennas. In many countriesthere is much discussion about the likely and unexplored health hazardsthat this may involve, not to mention the negative visual impact that anincreased number of the radio base stations introduce. As a result, manytelecom regulators have started to impose limitations on the number ofradio sites and the number of antennas that are allowed at a radio site.This is happening at the same time as telecommunication network vendorsare promoting the densification of radio base stations and going formore and smaller cells in a concept referred to as HeterogeneousNetworks.

The method of the present invention provides a solution to theabove-outlined problems. In general, the present invention demonstratesthat, by combining wireless technologies with power line communicationin a fixed-wireless convergence scheme, it is possible to provide aninexpensive, reliable and fast wireless communication with little impactregarding the frequency band used. The system of the present inventiontakes advantage of the synergy between wireless communication and powerline communication. Instead of having losses in the order of 80% thelosses may be substantially reduced and only be in the order of 15% sothat 85% or more of the original signal from the radio base stationreaches the end-user although the user may be located inside a house.

More particularly, the method is for providing broadband access into adwelling, A radio base station is provided that is in connection with apower-line communication (PLC) gateway. The radio base station transmitsan information signal to the PLC gateway. The PLC gateway receives thesignal and transmits the information signal via power-line to an insideof the dwelling. The PLC gateway may transmit the signal to a PLCrepeater. The PLC repeater transmits the signal to customer premiseequipment disposed inside the dwelling. The present invention includesthe radio base station sending a wireless signal to a fixed wirelessrouter. The wireless router receives the wireless signal and forwardsthe signal as a wired signal to the PLC gateway. The combination (fixedwireless router and PLC Gateway) would constitute the “Converger unit”,and where fixed-wireless convergence happens. The converger unit maycontain more than one wireless router serving several radio accessnetworks belonging to one or several telecom operators. The wirelesssignal is thus converted to the information signal which is wired. A PLCmodem may be positioned between a computer and an electrical plugconnected to an electrical outlet disposed inside the dwelling. The PLCmodem may also be connected to or incorporated in appliances orvehicles, hence offering a suitable solution for Smart-Gridapplications.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic overall view of the system of the presentinvention;

FIG. 2 is a schematic block diagram of some of the components of thesystem of the present invention when the radio base station is close tothe homes;

FIG. 3 is a schematic view of the converger unit of the presentinvention;

FIG. 4 is a schematic view of the data traffic flow through theconverger unit of the present invention;

FIG. 5 is a schematic overall view of the system of the presentinvention when the radio base station is close to the homes;

FIG. 6 is a schematic block diagram of some of the components of thesystem of the present invention when the radio base station is remotefrom the homes;

FIG. 7 is a schematic overall view of the system of the presentinvention when the radio base station is remote from the homes;

FIG. 8 is a schematic view of a PLC modem of the present inventionconnected to computers and tablets and whereby the modem is integratedin the power cable of desk-tops, lap-tops, tablets, and similar devicesin need of Internet connectivity;

FIG. 9 is a schematic view of the system of the present inventionconnected to appliances; and

FIG. 10 is a schematic view of the system of the present inventionconnected to vehicles.

DETAILED DESCRIPTION

One important purpose of the present invention is to transfer voice,video and other data through the air when it is efficient to do so andthen use the existing electricity power/utility network grid to transferthe data when obstacles such as walls must be penetrated.

FIG. 1 shows a system 100 that has a radio base station 102 in wirelesscommunication via the air with the device system 110 of the presentinvention. When the radio base station is close enough, thecommunication may be taken directly from the transmission modules orback-haul of the site i.e. at the radio base station, as discussed indetail below. Back-hauling may be used as a transport medium to transmitthe communication from the radio base station into switches or routers.The device system 110 in turn is in communication with the devices 104,106 and 108 via the already existing electric power grid, as explainedin detail below. Today's individual household may require as much as 10Mbps or more in order to simultaneously run television and computersover the broadband Internet. The use of the power lines into eachhousehold makes the transfer of data very inexpensive and practicalsince the transmission cables are already drawn, and electricity plugsare widely distributed in homes and other indoor locations. Connecting apower line communication (PLC) modem to any electricity plug enablesaccess to broadband Internet while serving home appliances such astelevisions. One problem is that transmitted signals get attenuated whenthey travel over electricity cables and through transformer stations tosuch an extent that the transfer of high-speed data over a longerdistance (such as over 1000 meters) is seriously hampered. However, whenit comes to short distances, such between the power meters in buildingsand power outlets at homes, PLC works very well and is able to delivertransmission speeds above 240 Mbps per user, depending on the PLCtechnology used. Examples of such technologies are the IEEE/OPERA andthe G.hn/G.hnem developed by ITU.

According to the present invention when an operator intends to provideindoors Internet access, the following elements are combined:

-   -   Established digital Mobile Telecom technology, for example        WCDMA/HSPA, LTS, LTE Advanced, or WiMAX;    -   Fixed wireless routers (FWR); and    -   PLC equipment in order to transmit or transport the signal        inside homes through electricity cables, and connect to Customer        Premises Equipment (CPE)/Modems.

The products involved should be combined and connected, in a veryadvanced manner to assure deployment on a large scale and to allow amultitude of telecom users to use the system of the present invention.

FIG. 2 shows device system 110 connected to a home 114. The home 114 hasa customer premises equipment (CPE) modem 116 connected to, for example,the television 104 and personal computer 106 and a telephone/fax 108.The CPE/modem 116 is in turn connected to a power line communicationdevice (PLC) 124. In this example, the home 114 is in close proximity toa radio base station antenna 126 that is in communication with awireless NW site backhaul 128. The PLC can already be installed withinthe site and connected directly to the backhaul equipment on site.

FIG. 3 shows a converger unit 300 wherein several WilePoLe FixedWireless Routers FWR:s 302 can connect with a PLC/BPL Gateway 304 in awell-integrated and protected manner, suitable for both indoor andoutdoor installations. Each router connects to a specific operator'snetwork to deliver data services, including Voice over IP (VoIP),Internet, and IP-TV.

The data traffic flows through the converger unit 300 is that wherebythe Fixed Wireless Routers (FWRs) 302 connect with the different RadioAccess Networks they belong to. It is then intended that data traffic toand from the Customer Premises Equipment (CPE) 306 belonging to eachoperator will flow through the FWR attached to that particular operatoras best shown in FIG. 4. Regarding chipset integration, it is possiblethat in a future scenario a higher level of integration combining thefixed wireless routers and the PLC Gateway equipment be done on chipsetlevel, whereby a hybrid chipset can be developed uniting the PLC (forexample: OPERA or ITU G.hn) chipset with that of the 3GPP chipset (forexample HSPA/LTE) or the WiMax chipset. Also, the InternationalTelecommunication Union (ITU) standardization organ has also developed astandard referred to as G.hn and G.hnem which defines networking overpower lines among other, and whereby signals can be transmitted overpower carrying electricity cables in addition to neutral ground cableswhen these are available.

FIG. 5 is a general view 129 that shows a high voltage power line 130connected to a low voltage transformer station 132 (such as 230Vsystems). The radio base station 134 is in direct communication with aPLC Gw 138 (PLC Gateway), that in turn, is in communication with a PLCRepeater 140 via a power line 136 that carries a current/voltage fromthe transformer 132. In other words, the communication signal 137 istransmitted directly from the transmission modules of the radio basestation 134 to the PLC Gw 138 when the PLC Gw 138 is very close to thebase station such as 5-30 meters or less. Preferably, the distance (D)between the PLC Gw 138 (and thus the station 134) and the PLC Repeater140 should be less than 1000 meters since the shorter the distance thelower performance loss of the data or information signal 137 transmittedin the electrical power grid or power line 136 leading into the insideof the dwelling or building 144. In this case, there is no need for awireless router to receive wireless signals from the radio base station134 since the PLC Gw is connected directly to the backhaul equipment inthe station 134. The signal (such as broadband) is distributed to homesdirectly from the site, without having to travel over the air interfacefrom the radio base station 134 in the last kilometer of thetransmission. The PLC repeater 140 is in communication with the CPEs 141a, 141 b, 141 c, 141 d and 141 e inside the multi-family building 144.As mentioned earlier, the building 144 should ideally be located within1 km from the PLC Gw 138 to keep the performance losses in the powerline 136 at a minimum. This example situation is ideal and provides thehighest performance. The sites act as access points to the IP networkand no wireless connection are needed between the base station 134 andthe CPEs 141 a-141 e disposed inside the building 144. As indicatedabove, this avoids the substantial loss of performance when wirelesssignals must travel through walls. This scenario is particularlysuitable when distances from radio sites to homes are very short and thesignal over the PLC does not have to travel through electricitytransformer stations. The signal is thereby received through anyelectricity plug in any room. The PLC modems are easily monitoredthrough a central O&M to deliver the required amount of data throughputper subscription.

FIG. 6 is a schematic view 150 that has a wireless network 152 connectedto a fixed wireless router (FWR) 154 that in turn are connected to theCPE/Modem 116 via the PLC 124. The CPE/modem 116 is then connected tocommunication devices such as the television 104, a personal computer106 and telephone/fax 108. More particularly, the view 150 describes asituation the home 114 is located at a far distance from the basestation sites, and therefore the PLC 124 would not be the ideal meansfor transporting the broadband signal due to the significant performancelosses over greater distances. One feature here is that the broadbandsignal is transmitted over the air interface to the fixed wirelessrouter 154 instead. The wireless network 152 connects to the FWR 154through a suitably positioned outdoor antenna system. This could, forexample, be a pole or a roof-top to provide the best signal transmissionquality (C/I) on both UL/DL. This in turn guarantees the highestpossible data throughput. The FWR 154 is preferably placed right afterthe electricity transformer station 132.

This throughput is then carried to the home 114 and other homes throughthe electricity installation (power meter—electricity outlets) using thePLC technology, as the transmitted signal from the FWR 154 may connectwith the PLC Gateway Device (PLC Gw) 138 in a one box concept. In otherwords, the wireless signal (135) is received by the FWR 154 from theradio base station 134 and converted to the wired signal 137 that isthen sent to the PLC Gw or gateway 138. The PLC gateway 138 connects tothe electricity network including the power line 136 and distributes thewired signal 137 to customers. Preferably, the homes should ideally belocated within 1 km from the FWR/PLC Gw box also. The signal is therebyreceived through any electricity plug in any room. The PLC modems areeasily monitored through a central O&M to deliver the required amount ofdata throughput per subscription.

FIG. 7 is a general view 170 that again shows the high voltage powerline 130 connected to a low voltage transformer station 132. The radiobase-station 134 is remotely positioned relative to the building 144.The transformer station 132 is in communication with a FWR/PLC Gw box174 via the power line 136. The box 174 is in communication with the PLCRepeater 140 also via the power line 136. Preferably, the distance (D)between the FWR/PLC Gw box 174 and the PLC Repeater 140 should be lessthan 1000 meters. Ideally, the box 174 may even be located on the roofof the building 144. The PLC Repeater 140 is then in communication withthe CPEs 141 a, 141 b, 141 c, 141 d and 141 e of the multi-familybuilding 144. The broadband/radio signal is distributed to the homes bytraveling through the air interface as a wireless signal 135 between theradio base-station 134 and an antenna 172 of the FWR/PLC Gw box 174which includes a combination of the Fixed Wireless Router/Terminal(Modem) or FWR/RF 154 and the PLC Gw 138. The performance loss of theair interface is kept to a minimum as the radio signal is capturedoutdoors, often in line-of-site. The building 144 should ideally belocated within 1 km from the box 174 to reduce the signal degradation inthe power line 136. This is particularly important regarding modulationtechniques of 4G and other high performance networks. This exampledemonstrates the usefulness in all rural areas but other areas may alsobenefit from the system of the present invention. Note that theconverger unit is preferably the combination of the FWR/PLC Gw box 174and the antenna system 172.

The deployment of the system of the present invention has the potentialof being expanded beyond households to cover any indoor environment. Itis hence conceivable that the system could be used in vehicles such asboats, trains, and airplanes. The system of the present invention mayalso prove to be a good compromise solution to handle futuremachine-to-machine communication.

The components of the system of the present invention are now describedin more details. The Fixed Wireless Routers (FWR) 154 and the Power-lineCommunication Gateway (PLC Gw) 138 may be combined in a modular one boxsolution i.e. FWR/PLC Gw box 174) and referred to as the “Converger”unit. The “Converger” unit box is preferably designed so that the FWR154 can be easily removed and replaced for maintenance or upgradepurpose.

The casing of the “Converger” unit box 174 should comply with thefollowing functional specifications:

-   -   Fully weather proof architecture, including lightning protection        and tolerance for ambient temperatures of −35° C. to +60° C. in        addition to humidity protection;    -   Passive and environmentally friendly cooling/heating;    -   Full insulation from electricity shock hazards, especially since        it will have to connect, on low-voltage electricity cables;    -   Resistant to destruction;    -   Protected opening for RF cable; and    -   The casing may include an integrated RF functionality, such, as        panel antenna or similar.

Preferably, the FWR 154 connects to an external directional antennasystem, ideally placed, outdoors at the top of a pole or a roof-top. Thepurpose is to enable good radio conditions and line-of-site. The antennacan also be designed in order to manage Multiple Input. Multiple Output(MIMO), Beam Forming, and other antenna techniques. If necessary, asignal booster may be used to strengthen the incoming signal. The FWRshould be designed with the following features:

-   -   Support radio redundancy;    -   Support external antenna(s) with MIMO capability, beam forming,        and possible future RF enhancements;    -   Support one multi-band RAN technology;    -   Support VoIP;    -   Support battery back-up;    -   Support incoming signal booster if such is found, necessary;    -   SIM card activation should be necessary, and operator/cell        locking mechanisms should be included;    -   Support for wide AC voltage range (80-250 V) and different DC        power alternatives such as 12V and 24V;    -   Full remote management; and    -   100/1000 Mbps Ethernet Connection (RJ45) interface or any other        suitable interface.

Moreover, the interface with the PLC Gw 138 should be designed in amanner to allow smooth replacement of the FWR 154 in a plug-and-playmanner. IP transport is the main mode of transmission over Ethernet at asuitable layer to enable maximum throughput. Both IP version 4 and IPversion 6 can be used although IP version 6 would be the preferredprotocol. The PLC should also benefit from the latest in the technologywith, for example, OFDM and other such suitable techniques. The PLC Gw138 should comply with the following requirements:

-   -   Support IP over Ethernet, for both IP V4 and IP V6;    -   Easy physical installation;    -   Small and slim design to fit in every installation environment;    -   Support for wide AC voltage range (80-250 V) and different DC        power alternatives such, as 12V and 24V;    -   Support Battery Back-up;    -   Full remote management;    -   Support OFDM; and    -   100/1000 Mbps Ethernet Connection (RJ45) interface with the        possibility of simultaneously connecting to more than one fixed        wireless router connected to different access technologies.

At the customer premises, the data signal is extracted from the homeelectricity plugs. This is an important part of the system of thepresent invention that should be managed correctly for successfulmassive deployment and that is technology agnostic. It is thereforepossible that:

-   -   Fixed Wireless Routers from different RAN technologies use the        same PLC equipment; and    -   Different routers from the same RAN technology but belonging to        different operators use the PLC equipment installed        Therefore the CPE should be able to:    -   Identify the end-users;    -   Identify the source of signals and allow the correct signal to        pass to the right end-user;    -   Regulate the data rate that can pass through it, so based on the        subscription type, it should be able to set an upper limit for        throughput;    -   Full remote management;    -   Support OFDM;    -   Support W-LAN with encryption;    -   Support RJ45 10/100 Mbps Ethernet interfaces;    -   Support USB contact interfaces;    -   Support IP Telephony/Voice over IP (VoIP); and    -   Support TV contact interfaces such as HDMI contact or other.

It is possible that a special modem be needed for special applicationssuch as the PLC modem integrated in the power cables of laptops,desktops, and other devices needing Internet connectivity. The specialmodem should have similar functionalities compared to the CPE:

-   -   Fixed Wireless Routers from different RAN technologies use the        same PLC equipment; and    -   Different routers from the same RAN technology but belonging to        different operators use the PLC equipment installed.        The special modem should be able to:    -   Identify the end-user;    -   Identity the source of signals and allow the correct signal to        pass to the right end-user;    -   Regulate the data rate that can pass through it, so based on the        subscription type, it should be able to set an upper limit for        throughput;    -   Full remote management;    -   Support OFDM; and    -   Support RJ45 contact interface;    -   Support of IP V4 and IP V6.

An operation and management system. (O&M) should be designed to act. asone single remote interface to all the components involved in the systemof the present invention. It should be designed to:

-   -   Connect to, control, and monitor the functionality of the        components, FWR, PLC, and CPE;    -   One single O&M center should be able to handle a large number of        invention devices (in the tens of thousands); and    -   It is recommended that it be based on a platform that is        commonly used in Telecom O&M.

In summary, the system of the present invention is a new conceptcombining wireless communication technologies with that of Power LineCommunication (PLC). The system is an effective concept for thedevelopment of countries and whereby motivation is provided to increasetelecom coverage as well as the reach of electricity grids to new areas.The system benefits all parties involved in telecommunications,equipment suppliers, operators, and end-users alike.

It is possible to use the special PLC modem in connection with poweringcomputers and even tablets. FIG. 8 is a schematic view 180 that has anAC power cord 182 that has one end connected to the special modem 184and AC/DC converter 186 and the other end connected to an electric plug191 at an outlet 193 on a wall. A cable 188 may be used to connect themodem 184 to the computer 190 (such as a battery powered laptop computeror tablet), while a DC power cord 192 may be used to connect theconverter 186 to the computer or tablet 190. Similarly, when there is noneed for the AC/DC converter then the power cord 182 extends directly tothe computer 194 (such as a desktop computer that is not batterypowered). The idea here is to build the special PLC modem 186 into powercables going to PCs and Desk Tops to assure Broadband connectivity. Thisis expected to be a practical means of assuring broadband connectivityas the system of the present invention becomes a widespread conceptthroughout the world. The present invention is not limited to PCs. It isalso possible to add a modem such as a WiTePoLe modem to the electricitysupply of a Tablet would be similar to doing the same for a PC. AWiTePoLe PLC modem may be inserted in the power supply cable thatprovides internet connectivity.

It is also possible to use the built-in PLC modem 184 in homeappliances. Machine-to-machine connectivity is the next frontier when itcomes to the telecom industry. Many home appliances manufacturers aredesigning their products to take benefit from the new smart gridconcept. Also, snack vending machines can be enhanced with communicationcapabilities. FIG. 9 shows a schematic view 196 of the system 198 of thepresent invention connected to various appliances and vending machines200 a-e. It is possible that the system of the present invention may beadopted as a compromise communication solution for home appliances andsnack vending machines manufacturers. This is especially valid shouldthe system of the present invention be able to successfully drive theexpansion of the electricity grid and telecom coverage to new areas.

Larger vehicles such as MPV, SUV, trains, airplanes, boats, and bussescould benefit from an adapted system solution whereby the internalelectricity cables of these vehicles may be used to transfer broadbandsignals, while connecting to wireless networks through routers withsuitably placed antennas. FIG. 10 is a schematic view 202 that has thesystem 204 of the present invention connected to various vehicles 206a-e. This will have to involve in certain cases special PLC equipmentthat works with DC power. The modem then connects to the standard DCoutlets found in cars and busses or normal outlets providing DC power.For the rest (trains, boats, airplanes), the normal PLC equipmentworking with AC power will be needed.

As the Pico and Femto RBS are progressively gaining widespread as officeand home access points, it remains in many regions a challenge toprovide these with the adequate IP connectivity to the core network. Thesystem of the present invention may be used here to provide thisconnectivity over a suitable radio access network (for example LTE) tobe used as a backhaul.

While the present invention has been described in accordance withpreferred compositions and embodiments, it is to be understood thatcertain substitutions and alterations may be made thereto withoutdeparting from the spirit and scope of the following claims.

1. A method for providing broadband access, comprising: providing aradio base station in connection with a power-line communication (PLC)gateway; the radio base station transmitting a wireless signal to awireless router, the wireless router forwarding an information signal tothe PLC gateway; and the PLC gateway receiving the information signaland transmitting the information signal via a power-line to via anoutlet to an PLC modem connected to the outlet at an inside of adwelling.
 2. The method according to claim 1 wherein the method furthercomprises the PLC gateway transmitting the signal to a PLC repeater. 3.The method according to claim 3 wherein the method further comprises thePLC repeater transmitting the signal to customer premise equipment viaan electric outlet disposed inside the dwelling.
 4. The method accordingto claim 1 wherein the method further comprises the radio base stationsending the wireless signal to an antenna.
 5. The method according toclaim 4 wherein the method further comprises the wireless routerreceiving the wireless signal via the antenna and forwarding the signalto the PLC gateway.
 6. The method according to claim 1 wherein themethod further comprises converting the wireless signal to theinformation signal which is wired.
 7. The method according to claim 1wherein the method further comprises positioning an electrical plug atone end of a power cord into the outlet connecting another end of thepower cord into a PLC modem between a computer or tablet.
 8. The methodaccording to claim 7 wherein the method further comprises connecting thePLC modem to appliances.
 9. The method according to claim 7 wherein themethod further comprises connecting the PLC modem to vehicles.